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There are more than 300 million people living in the U.S., and each person uses an average of 100 gallons of water every day. That water must be brought to us, and it must be taken away.

These are sobering facts I learned from an interesting documentary on PBS, “Liquid Assets: The Story of our Water Infrastructure.” Just 100 years ago it was difficult for people to imagine turning on the tap and getting clean water. Today, that is an expectation.

Water infrastructure is a modern engineering marvel. But because it is buried, we often take it for granted. The documentary explains that roads cave in and bridges fall apart so the concern is that the infrastructure that cannot be seen is also falling apart. It is old and has not been upgraded, replaced or fixed. Experts predict that by 2020, 85 percent of our current infrastructure will have reached the end of its useful life.

Our water infrastructure is vital for disease protection, fire protection, basic sanitation, economic development and for our quality of life. The documentary claims that we have about two million miles of pipe in this nation – an infrastructure that our great grandparents installed and one that has basically been unchanged since.

In the 1950s and ‘60s, there was a push to build wastewater treatment plants across the U.S. to protect public health. Today, with evolving technology, the waste travels through multiple stages of treatment removing tons of solids, settling out microscopic particles and introducing bacteria that consume and decompose the toxic materials.

In population centers like Los Angeles, the scope of this task is staggering. The Hyperion Sewage Treatment Plant serves four million people, processes 350 million gallons of sewage and removes 500 tons of solids daily. What happens if the infrastructure that protects the clean water coming in and transports the waste back out deteriorates?

Shirley Franklin, Mayor of Atlanta and diligent advocate of repairing the city’s water works, says, “You don’t put a roof on a house one time. You don’t fix the plumbing one time. You don’t get your hair done one time. If we don’t continue to invest in repairing our infrastructure for the next 20 years, we’ll find ourselves back at the same point when we didn’t have direct access to clean water. If we don’t protect our water, we will be without water. We will be without industry . . . we will be without jobs . . . we will be without a healthy economy. And our people will be sick. So, we don’t really have a choice.”

So what is being done about this critical issue? The first obstacle is the funding gap. Our original infrastructure was built on government subsidies. While municipalities are responsible for maintaining systems and source supply, the standards that protect water are established at the federal level. The next obstacle is the daunting task of repairing and replacing these complex systems.

Let us know what you think about our country’s aging infrastructure and look for continued coverage on this topic in Pumps & Systems in 2009.

Boosting and pipelining heavy crude oil is a classic example of the operating cost benefits of using screw pumps over conventional centrifugal pumps. Considering oil prices over the past year, production and transportation operating costs are more important than ever and likely to remain that way well into the future. Screw pumps are uniquely suited to this service, offering pump efficiencies in the 80% range while requiring little, if any, additional crude oil heating or dilution.

Power losses within multiple screw type pumps include volumetric, viscous and mechanical. The staging effects of screw pumps help minimize volumetric losses. Viscous shear losses are controlled by careful selection of operating speeds, typically in the 900 to 1800 RPM range. Mechanical losses from seals and bearings are usually a very small percentage of the total losses. Larger machines, including screw pumps, improve efficiency.

Multiple screw pumps have been used on heavy oil pipeline services since the 1950′s. Their capabilities and range of capacity has steadily improved and are now able to provide reasonable life on this demanding service while offering excellent operating efficiencies.

Check back in a few days for more detailed content on how screw pumps are an efficient option for crude oil pipelines.

For more information, contact Jim Brennan at

A lesson learned sixty years ago. When I was a little boy in the late 1940’s my father drove a 1939 Ford coupe, new cars were not available because of the war effort. The Ford coupes were good cars for the day however the windshield defrost system was almost nonexistent. Everyone added a small rubber bladed fan to the dash that blew air across the windshield acting as a defroster.

 Most fans were powered by 6 volt systems as 12 volt systems were not yet standard on today’s cars. Seatbelts were not even used in race cars let alone in passenger cars and kids road in the front seat when there was room. Many families only had one car which dad drove to work leaving mother home to take care of the house and kids. Many women didn’t even have driver licenses as there was no need. However, women whose husband was fighting in the war did drive and work outside the home to support the family and war effort.

 Enough of history — let me get back to the lesson. One cold winter day the family was going to town on Saturday for the weeks shopping trip and I got to ride in the front seat. Standing on the seat between mother and dad I was told not to put my fingers in the fan. Being a typical little boy what do you think I did? Of course I put my finger in the fan, now remember it was rubber so I didn’t get hurt only a sore finger. Years later I related that experience to NPSH.

 How does a sore finger relate to NPSH? The amount of energy I used to push my finger into the fan. NPSHr (required) is like the energy it takes to push liquid into the impeller eye of the impeller and just past the vane tips. NPSHa (available) is the energy in the piping system that is used to push the liquid into the eye of the impeller and just past the vane tips. That is how a sore finger years ago relates to NPSH.

So for non-engineers you now have an explanation of NPSH that you can use to explain NPSH to an engineer.

We went to press this week with the December issue of P&S, in which we ran a feature story on “The Impact of the Rising Cost of Raw Materials.” This has been a critical concern in our industry this year . . . in particular with the escalating costs of steel, copper and aluminum in combination with increased labor costs in China and throughout Asia.

Our industry has felt some relief in recent months, but it is a trend that deserves further attention in 2009.

Since we put the December issue to bed, I finally had a little time to read my second favorite periodical, Tennis Magazine. Ironically, I opened it directly to a feature story on  . . . you guessed it . . . the rising costs of raw materials used to manufacture tennis equipment. It is always interesting when perspective slaps you right in the face.

According to the article, the cost of carbon fiber (the primary building block of most racquets) has doubled in the past two years while materials used to make tennis balls (petroleum, rubber and resin) are also feeling the squeeze. Just like in the pump and rotating equipment industries, manufacturers and distributors are looking for ways to pass the increases on to the customer without pushing themselves completely off the market share map.

It may seem like a stretch, but it is all relative. Am I willing to pay $2.99 for a can of balls instead of $1.99?  Of course. Maybe I’ll wait till next year to buy another racquet (I have five of them, after all).

But when it comes to how these increases affect our industry, the price is significantly higher. When a pump goes down because a motor needs to be replaced and the cost of steel prevents that from happening, the impact is much more crucial.

  Series Crude Oil Pipeline Stations Using Rotary Positive Displacement Pumps 

The initiating station will have storage tanks/tank farm from which this station draws oil, sometimes via a low pressure boost pump unless the high pressure pumps are in close proximity to the tanks. The most common arrangement uses three 1/2 capacity pumps (one or two running, one a hot spare). This first station pumps the oil to the inlet of the next station. The receiving station has a bypass control valve from station discharge to station inlet. The bypass control valve senses station inlet pressure and bypasses whatever flow is necessary to maintain station inlet pressure at set point, usually 50 to 75 PSIG (3.5 to 5.2 BarG).

Normally, one of the second or subsequent station pumps is started. If station inlet pressure rises above set pressure, a second pump is started and the bypass control valve recirculates whatever volume of oil is necessary to maintain station inlet pressure at set point.

An alternative approach uses a variable speed drive to control pump speed maintaining station inlet pressure at the desired point. Since any combination of pumps could be running at the same time, all of the pumps should be equipped with variable speed drivers.

Regardless of method, each pump needs its own pressure relief valve (not shown below for clarity) connected from pump discharge to pump inlet. Their set pressure needs to be about 8 to 10 percent above normal station discharge pressure.